Startup scenarios in MW-class gyrotrons with diode and triode-type electron guns

Start-up scenarios for gyrotrons with diode and triode-type electron guns have been analyzed numerically by the use of code MAGY. Simulations have shown that in gyrotrons with diode-type electron guns a fast voltage rise allows one to avoid excitation of parasitic modes. In gyrotrons with triode-type electron guns, excitation of parasitic modes can be avoided by proper choice of the mod-anode voltage delay time.